From wearable ultrafiltration device to wearable artificial kidney

Since the inception of hemodialysis as a treatment for patients with chronic kidney disease, there have been designs created for portable, wearable or implantable devices to improve both quality of therapy delivered and patient quality of life.

We conducted a pilot proof- of- concept study in 8 stable adult hemodialysis patients using a wearable hemodialysis device with a sorbent-based regeneration dialysate system.

All patients were safely treated for 4-8 h. Ultrafiltration was successfully performed without any cardiovascular effects, with a reduction in extracellular fluid to total body fluid ratio (from 0.339 ± 0.003 to 0.335 ± 0.003 after treatment; p=0.002). Respective clearances (ml/min) were: 22.6 ± 1.8 for urea, 20.7 ± 1.8 for creatinine, 21.7 ± 1.8 for phosphate and 11.6 ± 1.8 for β(2)-microglobulin. Although the small solute clearances are much lower than for conventional intermittent hemodialysis, this device has been designed to operate for sustained periods, and therefore would be predicted to have equivalent small solute clearances to continuous dialysis treatments (CRRT) in the intensive setting. Safety mechanisms were shown to operate promptly in a case of a venous needle disconnection, and in cases of circuit clotting.

This was a pilot study designed to demonstrate the safety of a wearable hemodialysis device. In addition to confirming safety, we were able to confirm that the device not only had similar clearances to CRRT used in the intensive-care setting, but also increased clearances of middle molecules, such as β(2)-microglobulin and phosphate.